April 2007 - AMSAT-BB - mailman.amsat.org

Re: Cape-1 not Heard in IO92
by G0MRF＠aol.com 21 Apr '07

21 Apr '07

Hi. I also tried the morning passes over the uk today. I hoped that the satellite would recover having been in sunlight for long time before AOS. However, nothing heard. The last time I heard Cape 1 was at 22.14 on Wednesday April 18th with the satellite heading north from the UK having just emerged from eclipse over Spain on orbit 24. It sent its call - Which I misread as K5USA, followed by a string of seven zeros which faded into the noise. Jonathan. Can you tell us what the satellite is programmed to do in its safe modes? What should we be listening for now? Thanks David G0MRF In a message dated 21/04/2007 13:57:18 GMT Standard Time, g7hia(a)btinternet.com writes: Hi Jonathan and the list, Listened for 31126 (Cape-1?) this afternoon on the expected 13:00 UTC pass in range Central England. Used day 110.701138 keps taken from Space Track this morning. Minitored for over 30 minutes, nothing heard. 17 el X Yagi RHCP Radio YAESU FT847 73 John G7HIA

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Cape-1 not Heard in IO92
by john heath 21 Apr '07

21 Apr '07

Hi Jonathan and the list, Listened for 31126 (Cape-1?) this afternoon on the expected 13:00 UTC pass in range Central England. Used day 110.701138 keps taken from Space Track this morning. Minitored for over 30 minutes, nothing heard. 17 el X Yagi RHCP Radio YAESU FT847 73 John G7HIA

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Re: FO-29 Heard Sat Apr 21 2007 10:30 UTC
by Keith N4ZQ 21 Apr '07

21 Apr '07

Disregard my earlier post that FO-29 was heard this morning. After reading the many other post about it not being heard at all, it got me to thinking. A dangerous thing. So I reset my PC clock back to 10:25 UTC and fired up SatPC32, which I used for Doppler correction, and UA9OV CW Type to generate a CW CQ Beacon. Low and behold I heard myself again, but this time FO-29 was located over the South Pole. Seems I have a weak, self generated, birdie that occurs at or near one of FO-29 down link frequencies. My error !! Sorry if I got any hopes up and NOW I really pray FO-29 is fixable... Keith N4ZQ -- "Keith N4ZQ" <n4zq(a)netzero.net> wrote: Briefly, and I emphasize briefly, heard my own CW CQ on the 16 degree pass of FO-29 this morning. The signal only showed up about midway into the pass and lasted less than a minute. The satellite was barely in sunlight heading to eclipse. Signal was weak but sounded normal, no FMing noted. Can only hope it's recoverable. Keith N4ZQ EL88 Florida

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FO-29 remains "OFF"
by SV1BSX 21 Apr '07

21 Apr '07

Hi all, few minutes ago FO-29 passed overhead, between Italy-Greece (ORBIT #52724). The Satellite is definitely OFF. 73 de Mak, SV1BSX __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

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FO-29 not heard in JN35
by Piero Baudino 21 Apr '07

21 Apr '07

Hi all, ascending orbit 52722 starting at 11.45 UTC ending 11.59 UTC locator JN35UI max elevation 11 deg. nothing heard, no CW beacon, no transponder sat in sunlight Best '73 de Piero IZ1ERR

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Libertad-1 heard again in ZL
by Ian Ashley 21 Apr '07

21 Apr '07

Tonight I found Libertad-1 on two orbits, first at 10:55:30z and second at 12:37:20z on the 21st April, sending 5 packets each time. Signals were too weak to decode but I have made recordings which have been sent to the command stations. These are the Keplerian elements used OBJECT L 1 31128U 07012M 07110.63574250 -.00000048 00000-0 00000+0 0 78 2 31128 098.0856 185.7523 0103054 202.9718 156.7049 14.51822503 470 OBJECT M 1 31129U 07012N 07111.18688095 .00000384 00000-0 10000-3 0 137 2 31129 098.0832 186.2836 0102886 201.2880 158.4013 14.51906542 535 OBJECT N 1 31130U 07012P 07111.18706107 .00000711 00000-0 17610-3 0 20 2 31130 098.0921 186.2874 0102283 201.1355 158.5601 14.51839957 343 Libertad-1 is one of these, but at present they are all very close together. 73 Ian Ashley ZL1AOX

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FO-29 Heard Sat Apr 21 2007 10:30 UTC
by Keith N4ZQ 21 Apr '07

21 Apr '07

Briefly, and I emphasize briefly, heard my own CW CQ on the 16 degree pass of FO-29 this morning. The signal only showed up about midway into the pass and lasted less than a minute. The satellite was barely in sunlight heading to eclipse. Signal was weak but sounded normal, no FMing noted. Can only hope it's recoverable. Keith N4ZQ EL88 Florida

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K7XQ back on AMSAT-BB, P3E launch/status ?
by k7xq＠elite.net 21 Apr '07

21 Apr '07

Its been many years since I have been off this mail-list. Ive seen from the AMSAT Webpage that P3E satellite has been successfully launch and was wondering what the status of it was ? Also saw acouple of cubesats that were launched recently as well. I am in the process reconstructing the satellite portion of my shack and mobile setup and trying to figure out what bands and modes I should have available. Just picked up a AEA DSP-2232 but I suppose that manchester AFSK and PSK modes are no longer used on the more modern built satellites but thought I can still use the 1200/9600 AX25 modes. Looking forward to getting back on some of the birds again. Jeff K7XQ Atwater,CA. K7XQ webpage: http://www.elite.net/~k7xq/k7xq.html

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Re: Best arrangemet and best distance
by i8cvs 21 Apr '07

21 Apr '07

----- Original Message ----- From: "nader omer" <st2nh(a)yahoo.com> To: <amsat-bb(a)amsat.org> Sent: Friday, April 20, 2007 4:44 AM Subject: [amsat-bb] Best arrangemet and best distance Hello all I would like to know what the best arrangement and the best distances between vhf cross yagi antenna uhf cross yagi antenna l-band helical antenna s-band helical antenna over a one cross boom 73 de Nader -st2nh Hi Nader, ST2NH Any antenna has an aperture area that is the area around the antenna in wich the energy of the radio wave enters and is extracted from free space. For a dish the capture area is just the area of the mouth and obviously you don't want to put a dish inside to another dish For the same reason the capture areas of different antennas must be spaced so that they do not overlap. For a yagi the aperture area A can be "approximately" calculated using the following formula: / 2 G x /\ A = ------------- [ square meters] 4 x 3.14 Where: G = the isotropic gain expressed in factor (not in dBi ) / / \ = wavelenght expressed in meters Example for a 2 meters yagi with G= 13 dBi ( 20 time in factor) 2 2.07 x 20 A = ----------------- = 6.79 [square meters] 4 x 3.14 A circle with area A= 6.79 square meters has a radius R= SQR( 6.79 / 3.14) = 1.47 meters. This means that no other capture area generated by a different antenna must overlap the above 6.79 square meters extending up to about a distance of 1.47 meters from the boom. Since the aperture area A of any antenna is proportional to it's gain G it follows that for the same wavelenght greater is the gain and greater must be the distance from any other antenna in the system even if the antennas are designed for different frequencies. With this in mind and knowing the gain of each antenna it is possible to calculate the best distance from each antenna to the next one. Supposing that the gain of a 70 cm antenna is 16 dBi or about 40 time in power it follows that using the above formula A= 1.50 square meters and R= 0.69 meters If the 2 meters and 70 cm antennas are to be placed over the same support in the array than the distance between their booms must be not less than 1.47 + 0.69 = 2.16 meters and greater is better. For a yagi the capture area is not exacly a circle but an ellipse by the way the small error introduced by the above formula in the calculation of A can be accepted. For accurate calculation of the aperture area A in a yagi the equations discussed in the following article are recommended: " Staking Yagis is a Science " by Steve Powlishen, K1FO, Ham Radio Magazine May 1985 If someone is interested on this matter and cannot find the original article I can send by email a 5 MB + zipped file. 73" de i8CVS Domenico

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FO-20 Pass 52,717
by W7TYN 21 Apr '07

21 Apr '07

The FO-29 (V/U) transponder was off between 23:11 to 23:32 UTC 2007 April 20 when monitored from CN85om(Portland). The-70 cm beacon was not heard . This was an overhead pass of which I normally can hear the receiver noise floor. I worked WA8SME on The 15 of April on a simular pass and the bird sounded normal. 73 W7TYN AMSAT #03951

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